This invention relates to a printhead assembly. More particularly, the invention relates to a pagewidth inkjet printhead assembly.
According to the invention there is provided a printhead system comprising: a plurality of printhead assemblies aligned in end-to-end relationship, each printhead assembly including a plurality of printhead modules wherein the printhead modules are arranged in end-to-end relationship and are angled with respect to a longitudinal axis of the assembly such that printhead chips of adjacent modules overlap in a direction transversely to a direction of movement of print media past the assemblies.
The printhead module at one end of each assembly may have a projecting portion which projects beyond an end of its assembly and the printhead module at the other end has a recessed portion to receive the projecting portion of the printhead module at said one end of an adjacent assembly.
The printhead module may comprise a microelec-tromechanical printhead chip comprised of a number of inkjet nozzles, the nozzles of overlapping portions of adjacent modules to be used being digitally selected.
The angle of the printhead modules relative to the longitudinal axis of the assembly may be selected depending on a print pattern required. Each printhead module may have approximately 1587 dots per inch (dpi). To simulate 1600 dpi printing the printheads may be angled at approximately 7xc2x0 to the longitudinal axis, more specifically 7.17xc2x0.
Each assembly may include a chassis and an ink reservoir mounted on the chassis, the printhead modules of the assembly being attached to the ink reservoir. Preferably, the modules are releasably attached to the ink reservoir.
The assembly may include an ink supply system for supplying ink to the reservoirs of each assembly.
The chassis may be a rigid chassis for imparting torsional rigidity to each assembly.
The ink reservoir of each assembly may have ink inlet nozzles at one end and sealable air bleeding openings at an opposed end.